di·​ag·​no·​sis | \ˌdī-ig-ˈnō-səs, -əg-\
plural diagnoses\ -​ˌsēz \

Definition of diagnosis 

1a : the art or act of identifying a disease from its signs and symptoms

b : the decision reached by diagnosis the doctor's diagnosis

2a : investigation or analysis of the cause or nature of a condition, situation, or problem diagnosis of engine trouble

b : a statement or conclusion from such an analysis

3 biology : a concise technical description of a taxon

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Examples of diagnosis in a Sentence

The unusual combination of symptoms made accurate diagnosis difficult. She is an expert in the diagnosis and treatment of eye diseases. The diagnosis was a mild concussion. His doctor made an initial diagnosis of pneumonia. The committee published its diagnosis of the problems affecting urban schools.
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Recent Examples on the Web

In recent years, Ohio lawmakers have limited abortions by restricting them to earlier in a pregnancy or banning them after a diagnosis of Down syndrome. Jessie Balmert, Cincinnati.com, "New GOP-backed bill would ban abortion in Ohio," 19 Mar. 2018 Since her diagnosis, both her sister and niece (a mother of four in her 30s) have been diagnosed with ovarian cancer. Darcel Rockett, chicagotribune.com, "'If I lived on the North Side': Neighborhood may matter more than race in breast cancer survival rates," 9 July 2018 Michaelson was released from his Minnesota prison in March 2017, without getting any treatment for hepatitis C, almost seven years since his diagnosis. Washington Post, "State Prisons Fail To Offer Cure To 144,000 Inmates With Deadly Hepatitis C," 9 July 2018 Paris, Madrid, Gibraltar, and all over Switzerland—since his diagnosis. Cassie Shortsleeve, Condé Nast Traveler, "What It’s Really Like to Travel With Alzheimer’s," 28 June 2018 And so, in the months since my own diagnosis, my response has been to try and look outwards as well as inwards. Aaron Gilbreath, Longreads, "The Inward Empire," 27 June 2018 Owens entrusted Wiegand to break the news of his battle with Parkinson’s disease in 2014, after helping keep it a secret since his diagnosis in 2001. Ben Fong-torres, SFChronicle.com, "Listeners mourn loss of ‘Acoustic Sunrise’," 25 June 2018 Since McCain's diagnosis, Ducey has refused to engage in speculation about a potential appointment. Yvonne Wingett Sanchez, azcentral, "Ducey's office: 'Obsession' with who will get McCain's Senate seat is 'disgraceful'," 30 May 2018 McCain has amplified his call for more civil politics since his diagnosis in July with glioblastoma. Laurie Kellman, BostonGlobe.com, "In Ariz., John McCain gets visits from Biden, Graham after surgery," 5 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diagnosis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of diagnosis

1634, in the meaning defined at sense 1a

History and Etymology for diagnosis

New Latin, from Greek diagnōsis, from diagignōskein to distinguish, from dia- + gignōskein to know — more at know

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Statistics for diagnosis

Last Updated

1 Nov 2018

Look-up Popularity

Time Traveler for diagnosis

The first known use of diagnosis was in 1634

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More Definitions for diagnosis



English Language Learners Definition of diagnosis

: the act of identifying a disease, illness, or problem by examining someone or something

: a statement or conclusion that describes the reason for a disease, illness, or problem


di·​ag·​no·​sis | \ˌdī-əg-ˈnō-səs \
plural diagnoses\ -​ˌsēz \

Kids Definition of diagnosis

1 : the act of recognizing a disease from its signs and symptoms She specialized in the diagnosis and treatment of eye diseases.

2 : the conclusion that is reached following examination and testing The diagnosis was pneumonia.


di·​ag·​no·​sis | \ˌdī-ig-ˈnō-səs, -əg- \
plural diagnoses\ -​ˌsēz \

Medical Definition of diagnosis 

1a : the art or act of identifying a disease from its signs and symptoms

b : the decision reached by diagnosis a diagnosis of pneumonia

2 : a concise technical description of a taxon

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Comments on diagnosis

What made you want to look up diagnosis? Please tell us where you read or heard it (including the quote, if possible).


obstinately defiant of authority

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